New quinolones are promising agents for use in the treatment of bone and joint infections because of their broad spectrum of activity against staphylococcal strains as well as gram-negative bacteria. Their pharmacologic properties and their availability for oral administration make them the drugs of choice in the treatment of such chronic infections. Pefloxacin and ciprofloxacin are the principal quinolones that have been evaluated with respect to the treatment of bone and joint infections. In the literature cited the mean rates of bacteriologic and clinical response among patients treated with pefloxacin and ciprofloxacin were 87.6% and 73%, respectively, whereas failure of therapy were due to the persistence of the causative organisms (5% and 15% of the cases, respectively) or to the emergence of resistant mutant strains (15% and 12% of the cases, respectively). Development of resistance to the quinolones--especially in staphylococci, Pseudomonas aeruginosa, Serratia, Enterobacter species, and Klebsiella pneumoniae--is a problem that can be reduced by the intelligent use of these potent agents in spite of the ease of their administration. Therapy that combines new quinolones with other antibiotics should prevent the emergence of resistant mutants, but this hypothesis has to be assessed in large studies.